Manganese ore can be processed by crushing, classifying particle size and washing to remove a fine fraction, which is discarded as tailing. However, with the exhaustion of high grade manganese ore, mining industries face the challenge of benefiting and handling more complex ores and reprocessing tailings of high manganese content ores.
Usually manganese ores beneficiation flowcharts consist primarily of fragmentation and particle size classification, by exploiting only the richest and relatively coarse fractions, which are products that are called “granulated” and “sinter feed.” The finer particle size fraction (below about 0.150 mm) is typically discarded as tailing for not being noble and also due to the fact that the current equipment/beneficiation operations are not suitable for the recovery of this finer particle size fraction.
The fine fractions which constitute the tailings of the current processing circuits and which are also derived from the lithologies “Tabular Pelite” (PETB), Pelite Siltite (PEST), Detritic (DETR), Rich Pelite (PERC) or Metallurgical Bioxide (BXME) are known for their low manganese content. According to the state of the art for the ores containing manganese a direct anionic flotation process is preferred for the recovery (and concentration) of manganese. Nevertheless, until now no results in terms of adequate manganese liberation can be identified encouraging the persistence in the use or development of this concentration route. In fact, the direct anionic flotation in basic medium of the manganese minerals was not successful. In this way, the need for a better manganese recovery (and concentration) process still remains in the current state of the art.
In this context it is desirable to develop alternative flowcharts and concentration routes for these wastes as a complement to current processes in order to increase the global recovery of manganese as well as to reduce the environmental impact of disposal of this finer particle size fraction.